FEL2011 - List of Keywords (background)

Paper	Title	Other Keywords	Page
WEPB22	An Optical Streaking Method for Measuring Femtosecond Electron Bunches	laser, electron, wiggler, FEL	431
	Y.T. Ding, K.L.F. Bane, Z. Huang SLAC, Menlo Park, California, USA
	The measurement of the ultra-short electron bunch on the femotosecond time scale constitutes a very challenging problem. In the X-ray free electron laser facilities such as the Linac Coherent Light Source (LCLS), generation of a sub-ten femtoseconds electron beam at low charge operation mode is possible, based on indirect measurements and computer simulations. Direct measurements are not available due to the resolution limit of the present diagnostics. We propose a new method based on the energy modulation of the ultra-short electron bunch by interacting with an optical laser in a short wiggler. Compared with a laser-based transverse deflector, which requires the laser wavelength much longer than the electron bunch length, here we propose a scheme to use a laser with its wavelength shorter than the electron bunch length, where the slope on the laser intensity envelope has been used to help distinguish the different periods. The calibration is simple and it is possible to reconstruct the bunch longitudinal profile from a single shot measurement.

THOC4	Transverse Size and Distribution of FEL X-ray Radiation of the LCLS	simulation, undulator, electron, FEL	465
	J.L. Turner, F.-J. Decker, Y.T. Ding, P. Emma, J.C. Frisch, K. Horovitz, Z. Huang, R.H. Iverson, J. Krzywinski, H. Loos, M. Messerschmidt, S.P. Moeller, H.-D. Nuhn, D.F. Ratner, J.J. Welch, J. Wu SLAC, Menlo Park, California, USA
	Funding: Work supported by U.S. Department of Energy, Office of Basic Energy Sciences, under Contract DE-AC02-76SF00515 Understanding and controlling the transverse size and distribution of FEL X-ray radiation of the LCLS at the SLAC National Accelerator Laboratory is discussed. Understanding divergence, source size, and distributions under various conditions is a convolution of many effects such as the electron distribution, the undulator alignment, micro-bunching suppression, and beta-match. Measurements of transverse size along the X-ray pulse and other studies designed to sort out the dominant effects are presented and discussed.
	Slides THOC4 [1.874 MB]

Paper

Title

Other Keywords

Page

WEPB22

An Optical Streaking Method for Measuring Femtosecond Electron Bunches

laser, electron, wiggler, FEL

431

Y.T. Ding, K.L.F. Bane, Z. Huang
SLAC, Menlo Park, California, USA

The measurement of the ultra-short electron bunch on the femotosecond time scale constitutes a very challenging problem. In the X-ray free electron laser facilities such as the Linac Coherent Light Source (LCLS), generation of a sub-ten femtoseconds electron beam at low charge operation mode is possible, based on indirect measurements and computer simulations. Direct measurements are not available due to the resolution limit of the present diagnostics. We propose a new method based on the energy modulation of the ultra-short electron bunch by interacting with an optical laser in a short wiggler. Compared with a laser-based transverse deflector, which requires the laser wavelength much longer than the electron bunch length, here we propose a scheme to use a laser with its wavelength shorter than the electron bunch length, where the slope on the laser intensity envelope has been used to help distinguish the different periods. The calibration is simple and it is possible to reconstruct the bunch longitudinal profile from a single shot measurement.

THOC4

Transverse Size and Distribution of FEL X-ray Radiation of the LCLS

simulation, undulator, electron, FEL

465

J.L. Turner, F.-J. Decker, Y.T. Ding, P. Emma, J.C. Frisch, K. Horovitz, Z. Huang, R.H. Iverson, J. Krzywinski, H. Loos, M. Messerschmidt, S.P. Moeller, H.-D. Nuhn, D.F. Ratner, J.J. Welch, J. Wu
SLAC, Menlo Park, California, USA

Funding: Work supported by U.S. Department of Energy, Office of Basic Energy Sciences, under Contract DE-AC02-76SF00515
Understanding and controlling the transverse size and distribution of FEL X-ray radiation of the LCLS at the SLAC National Accelerator Laboratory is discussed. Understanding divergence, source size, and distributions under various conditions is a convolution of many effects such as the electron distribution, the undulator alignment, micro-bunching suppression, and beta-match. Measurements of transverse size along the X-ray pulse and other studies designed to sort out the dominant effects are presented and discussed.

Slides THOC4 [1.874 MB]